Wireless-telephone tube sending station



Oct. 16, 1928.

H. .CHIREIX WIRELESS TELEPHONE TUBE SENDING STATION Filed July 23, 1923AMPLIFIER HFGENERATOR avweutoz $51 Yam, Gum/mug);

NR! CHIRElX Md 4 41M Patented Oct. 16, 1928.

- UNITED STATES HENRI CHIREIX OF PARIS, FRANCE.

wrnELEss-TELEPHoNE TUBE SENDING STATION. i

Application filed July 23, 1923, Serial No. 658,181, and in FranceOctober 4, 1922.

The" object of the present invention is to improve the emission obtainedby means of tube stations when thesetubes are fed from an alternatingcurrent source through the agency of a rectifying means. It happensthat, notwithstanding the care taken in rectifying the supply current,this current is not perfectly continuous. Onthe other hand, even if thecircuits are very carefully installed, there will always remain aresidual electrostatic and electromagnetic induction effect. Finally,due to the fact that the filaments are heated by analternating current,their calorific inertia mustbe taken into consi'deration, and thedifferences of potential between grid and filament, and plate andfilament vary in accordance with the frequency of the supply current.Due to these causes, one or several sounds will be heard at thereceiving station, said sounds correspondingto' the frequency of thefeeding current and its harmonics. This sound is particularlyannoying incase music or singing is transmitted.

In accordance with the present invention, this tone is suppressed bysuperimposing on the microphonic potential variations an E. M. F.'whichis synchronous with that of the supply source, and the phase andamplitude of which are variable; Obviously, the introduction of thiscompensating E. M. F. may be effected at any suitablepoint in the.modulating circuit, and by any suitable electrical connection(conductive, inductive, capacitive The invention will be more readilyunderstood from the following description of an exemplification which isschematically illustrated in the figure of the drawings. 1 is thepick-up microphone with its source 2 and coupling transformer 3. 4 is amicrophonie current amplifier. 5 is a coupling transformer providedbetween the transmitter circuit and the modulating circuit of theapparatus generating the continuous waves and schematically illustratedat '6. The system radiating the modulated waves is shown at 7 (antenna).In accordance with the present invention, an M. F. is introduced intothe circuit traversed by the transmitter current e. g. at 8 through theagency of a variable coupling transformer shown at 9. This E. M. F. isof the same frequency as that of the alternating current generator whichis feeding the tubes of the high frequency generator 6, the phase of the'E. M. F. being coil- 15 provided in this field may be pointed in thedesired direction.

Obviously, the invention may be subjected to numerous variations. Incertain cases in which it is desired to suppress also the'efiect of theharmonics of the main tone, as many similar arrangements should besuperimposed as there are harmonics to be suppressed. Thejuxtapositionof these arrangements'will make possible various circuitcombinations and simplifications. Harmonic opposing E. M. F.s maybegenerated in the supply source by any suitable frequency multiplyingmeans (particularly by means of tube systems arranged to double thefrequency). Finally, it should be noted that the above describedcircuits may be shielded with respect to the considerable inductioneffects of the high frequencies by providing a casing 16 of conductingmaterial which is suitably grounded} and forms an electrostatic andelectromagnetic screen around. the cirwits and apparatus traversed bythe 'c'0m-' pe'nsating currents. Furthermore, it is advisable to providevery long insulated knobs for'operating the movable elements (variometer15, coil 9, etc.), or equivalentdistant controlling means so as to avoidthe disturbances in the tuning that may be caused by the approach of theoperator,

Having described my invention, what I claim is:

1. The method of eliminating feed frequency tones and harmonics thereofin modulating systems utilizing alternating or rectified currents whichconsists in deriving from such currents another current and supplyingsuch current to the modulating current in a manner to neutralizethefeedfrequency tones.

2. The method of neutralizing undesired frequency in modulating systemutilizing fluctuating currents which consists in deriving from suchfluctuating currents a second current, introducing such current into theclrcuit traversed by the .modulatlng current and adjusting the phase ofthe current so introduced in a manner to neutralize the undesiredfrequencies.

3. In a radio signalling system, an oscillator, means for modulating theoutput of said oscillator, means for supplying power to said oscillator,Jeans in shunt with said oscillator for producing -a rotating field,means arranged to have currents induced therein by the action of saidfield and means for supplying such currents to said modulatin means.

4. In a radio signalling system, a transmission conductor, an oscillatorfor energizing said conductor, means for modulating the output of saidoscillator, a source for supplying power to said oscillator, meansactuated by said source for producing a rotating field, means forderiving from such field a secondary current and means for combiningsuch current with the current to be modulated.

5. In radio signalling apparatus, the com bination of a transmissionconductor, an oscillator for energizing said conductor, means formodulating the output of said oscillator, a source of power forenergizing said oscillator, means associated therewith for producing analternating current of any desired phase relation with respect to thecurrent delivered by said source, means for combining such current withthe modulating current and means for varying the intensity of suchcurrent.

6. In radio signalling apparatus, the combination of a transmissionconductor, an oscillator for energizing said conductor, means formodulating the output of said oscillator, a source for feeding saidoscillator, phase shifting means for producing a current having adesired phase relation wlth the oscillator current and variable couplingmeans for combining such current with the modulating current. I

7 In a radio system a transmission conductor, means for producingoscillations in said conductor, means for modulating said oscillationswith speech currents, means for producing a current in any desired phaserelationship to said oscillations and means for combining said lastnamed current with said modulating speech currents.

8. In a radio system, a transmission conductor, an oscillator forproducing oscillations therein, means for modulating said oscillations,a source of alternating current energy for supplying power to saidoscillator, a circuit connected to said source including means of thesame frequency said modulating means to cause a current flow in saidmodulating means of the same.

frequency as'said source and in any desired phase relationship. r

9. In a radio system an oscillator, a source of low frequencyalternating current for feeding said oscillator, means for modulatingthe output of said oscillatonand means connected with said. source forcausing current flow in said modulating means of the same frequency assaid source, and in any desired phase relationship.

10. In a radio system an oscillator, a source of low frequencyalternating current for feeding said oscillator, means for modulatingthe output of said oscillator, and means for causing current flow insaid modulator of the same frequency as said source, said last namedmeans including means for varying the intensity of said current, andmeans for varying the phase of said current. V

' V. HENRI CHIREIX.

for producing a rotating field as said source and ad ustable means insaid field connected to.

